Lincoln Electric SVM136-A service manual Mounting of Stud Type Diodes, To Aluminum Heat Sinks

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Section TOC

Master TOC

F-45

F-45

TROUBLESHOOTING & REPAIR

MOUNTING OF STUD TYPE DIODES

TO ALUMINUM HEAT SINKS (continued)

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PROCEDURE

1.Remove the main input supply power to the machine.

2.With the 5/16” nut driver, remove the case top and sides.

3.Loosen the appropriate diode nut and remove the diode that is to be replaced.

4.Clean the area on the heat sink around the diode mounting surface using a putty knife or similar tool. DO NOT SCRATCH THE DIODE MOUNTING SURFACE.

5.Polish each heat sink’s mounting surface using No. 000 fine steel wool. Wipe the sur- face clean with a lint-free cloth or paper towel.

6.Inspect the mounting surfaces of each new diode. Remove all burrs and wipe clean. Do not use steel wool or any abrasive cleanser on the diode mounting surface.

7.Apply a thin (0.003” to 0.007”) uniform layer of E1868 (Dow Corning 340) heat sink com- pound to the heat sink mounting surface.

a.Do not apply compound to the diode stud or mounting threads.

b.The diode threads must be clean and free of defects so that the nut can be fin- ger tightened before applying torque. A “slip” type torque wrench must be used to tighten the diode nut.

8.Tighten the diode nuts to the specifications in the following table.

a.Start the nuts for diodes with steel studs by hand and then torque them accord- ing to the following table.

b.Run the nuts for diodes with copper studs on all the way by hand then torque them according to the following table.

c.Turn the nuts a minimum of 1/2 turn more while torquing.

9.Install the case top and sides.

DIODE STUD	FOOT-	INCH-
SIZE	POUNDS	POUNDS

3/4-16	25-27	300-324
3/8-24	10±.5	125+0/-5
1/4-28		22-25

IDEALARC CV-400

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Contents Idealarc CV-400 California Proposition 65 Warnings SafetyElectric Shock can kill Cylinder may explode if damaged Sûreté Pour Soudage a L’Arc Précautions DE SûretéMaster Table of Contents for ALL Sections Table of Contents Installation Section Technical Specifications Idealarc CV-400 InstallationLocation and Ventilation Safety PrecautionsLifting Input Supply Connections Ground ConnectionReturn to Input Wire and Fuse SizeConnect Electrode and Work Leads to Output Terminals Reconnect Procedure Output ConnectionsFigure A.5 Output Terminal Connections Connect Wire Feeders Table of Contents Operation Section Operation Safety InstructionsOperating Instructions Design Features Operational Features and ControlsGeneral Description Recommended ProcessesLimitations Welding CapabilityFigure B.1 Case Front Controls Controls and SettingsWelding Operation Remote ControlLocal Control Overload Protection Auxiliary PowerIdealarc CV-400 Table of Contents Accessories Factory Installed Options OPTIONS/ACCESSORIESField Installed Options Connecting the NA-3 to the Idealarc CV-400 Automatic Wire FeedersFeederterminal Connecting the NA-5 to the Idealarc CV-400Accessories Connecting the LN-7 to the Idealarc CV-400 Terminal Strip Semiautomatic Wire FeedersConnecting the LN-8 or LN-9 to the Idealarc CV-400 Idealarc CV-400 Table of Contents Maintenance Return to Return to Section TOC Safety Precautions Routine and Periodic MaintenanceFigure D.1 Idealarc CV-400 Table of Contents Theory of Operation Section Input Line VOLTAGE, Contactor and Main Transformer Theory of OperationOutput CONTROL, Rectification and Feedback Figure E.4 CV-400 Trigger and Thermal Light Circuit Protective Devices CircuitsFigure E.5 SCR Operation SCR OperationIdealarc CV-400 Table of Contents Troubleshooting & Repair Section HOW to USE Troubleshooting Guide Troubleshooting & RepairElectric Shock can kill PC Board Troubleshooting ProceduresOutput Problems Troubleshooting GuideOutput Problems SCR/Diode Perform the SCR/Diode Bridge SCR/Diode Rectifier Bridge Test Welding Problems Description Control Transformer T2 Voltage TestMaterials Needed Control Transformer T2 Voltage Test Test ProcedureRight Side View Input Contactor Test Input Contactor Test Figure F.4 Input Contactor Test Connections Test for Contact ContinuityMain Transformer T1 Voltage Test Main Transformer T1 Voltage Test Figure F.6 Main Secondary Lead Test Points Blank Main Transformer T1 Voltage Test Static SCR/DIODE Rectifier Bridge Test Static SCR/DIODE Rectifier Bridge Test SCR Anode Remove ANY Insulating Paint Cathode SCR Active SCR Test Active SCR Test Figure F.15 Heat Sink Test Points Figure F.16 SCR Tester Circuit and SCR Connections Normal Open Circuit Voltage Waveform Maximum Output Setting no LoadTypical Output Voltage Waveform Machine Loaded Typical SCR Gate Voltage Waveform Maximum Output Setting no LoadONE Output SCR not Functioning Abnormal Output Voltage Waveform Machine LoadedDescription Input Contactor CR1 CLEANING/REPLACEMENTContactor Replacement Procedure Cleaning ProcedureFAN Motor and Blade Removal and Replacement Procedure FAN Motor and Blade Removal and ReplacementSCR/DIODE Rectifier Assembly Removal and Replacement Removal and Replacement SCR/DIODE Rectifier AssemblySCR Removal and Replacement SCR Removal and Replacement Figure F.21 1/2 Wide Leaf Spring Procedure for the 1/2 Inch Wide SpringClamping Procedure For 1/4-20 CAP Screws Clamping Procedure For 1/4-28 CAP ScrewsInch Wide Spring Procedure forAfter Replacing the SCRs Mounting of Stud Type Diodes To Aluminum Heat Sinks To Aluminum Heat Sinks Mounting of Stud Type DiodesMain Transformer Removal and Replacement Removal of Lift Bail Main Transformer Removal & ReplacementFigure F.26 Choke Removal Removal of Choke and TOP Iron AssemblyFigure F.27 Epoxy MIX Application Areas Reassembly of Transformer CoilsFigure F.28 Coil Lead Placement Figure F.30 Primary Thermostat Location Reassemble the Lift Bail Reassembling the Main Transformer Into the MachineInput Idle Amps and Watts Retest After RepairOpen Circuit Voltages Welding Output Load TestIdealarc CV-400 Section G Electrical DiagramsWiring Diagram Codes 10084, 10085 Wiring Diagram Code Control PC Board G2629-1 Layout Control PC Board G2629-1 Schematic Snubber Snubber PC Board M15370-3 Schematic Idealarc CV-400